Nitrogen and vanadium alloyed powder metallurgy (PM) tool steels attained a considerable interest because of their unique combination of high hardness, high wear resistance and excellent galling resistance. These steels have a wide range of applications where the predominant failure mechanisms are adhesive wear or galling. Typical areas of application include blanking and forming, fine blanking, cold extrusion, deep drawing and powder pressing. The basic steel composition is atomized, subjected to nitrogenation and thereafter the powder is filled into a capsule and subjected to hot isostatic pressing (HIP) in order to produce an isotropic steel. A high performance steel produced in this way is VANCRON® 40. It has high carbon, nitrogen and vanadium contents and is also alloyed with substantial amounts of Cr, Mo and W, which result in a microstructure comprising hard phases of the type MX (14 vol. %) and M6C (5 vol. %). The steel is described in WO 00/79015 A1.
Although VANCRON® 40 has a very attractive property profile there is a continuous strive for improvements of the tool material in order to further improve the surface quality of the products produced as well as to extend the tool life, in particular under severe working conditions, where galling is the main problem.